Phytolith analysis of Chusquea ramosissima Lindm. (Poaceae: Bambusoideae) and associated soils

Abstract

Chusquea ramosissima Lindm. is dominant in the understory of the Misiones province forests (Argentina); it colonizes open natural areas and gaps created by timber extraction. The aim of this study is to analyze both the phytolith assemblage produced by leaves, culms, and roots of C. ramosissima and the one deposited on soil surface. This information will be used in future phytolith studies of the Misiones forest soils, which will contribute to understanding the dynamics of this species in the past. Phytoliths were extracted from plant organs by using a calcination technique and morphotypes were identified in plant tissue by anatomical observations. Soil samples were collected from two sites with a different history of use and vegetal cover. The three organs produced different phytolith morphotypes; leaf was the main producer. From the soil samples, only leaf phytoliths were observed. Although concave dumb-bells are the characteristic phytoliths of C. ramosissima, their greater robustness and higher preservation in soil-even where this species is nowadays absent-do not help to discriminate clearly between sites with and lacking this species. On the other hand, the panicoid dumb-bell (bilobated flat/concave ends short cell) and Chusquea bulliform (cubic/parallepipedal bulliform cell) phytoliths seem to be more sensitive to changes in the presence/absence of this species. Results from this research will provide useful information for future studies of late Pleistocene-Holocene reconstruction in this region.